kernel: add support for linux 3.2.1

[openwrt.git] / target / linux / generic / patches-3.2 / 201-extra_optimization.patch

diff --git a/target/linux/generic/patches-3.2/201-extra_optimization.patch b/target/linux/generic/patches-3.2/201-extra_optimization.patch
new file mode 100644 (file)
index 0000000..6fe8b09
--- /dev/null
+++ b/target/linux/generic/patches-3.2/201-extra_optimization.patch
@@ -0,0 +1,24 @@
+--- a/Makefile
++++ b/Makefile
+@@ -559,9 +559,9 @@ endif # $(dot-config)
+ all: vmlinux
+ 
+ ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
+-KBUILD_CFLAGS += -Os
++KBUILD_CFLAGS += -Os -fno-caller-saves
+ else
+-KBUILD_CFLAGS += -O2
++KBUILD_CFLAGS += -O2 -fno-reorder-blocks -fno-tree-ch -fno-caller-saves
+ endif
+ 
+ include $(srctree)/arch/$(SRCARCH)/Makefile
+@@ -620,6 +620,9 @@ endif
+ NOSTDINC_FLAGS += -nostdinc -isystem $(shell $(CC) -print-file-name=include)
+ CHECKFLAGS     += $(NOSTDINC_FLAGS)
+ 
++# improve gcc optimization
++CFLAGS += $(call cc-option,-funit-at-a-time,)
++
+ # warn about C99 declaration after statement
+ KBUILD_CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
+